A heat exchanger core includes a first side, a second side, a third side, and a fourth side. A first layer includes a first width extending in a first direction, a first length extending in a second direction, a first height extending in a third direction, and a first plurality of passages, which extend from an inlet to an outlet. A second layer includes a second width extending in the first direction, a second length extending in the second direction, a second height extending in the third direction, and a second plurality of passages extending from the first side to the second side. The first and second plurality of passages are adjacent to one another. The first and second plurality of passages include a sinusoidal profile in the third direction and a sinusoidal profile in the first direction.
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1. A heat exchanger core comprising:
a first side;
a second side, opposite the first side;
a third side;
a fourth side, opposite third side, wherein the third and fourth side extend from the first side to the second side;
a first layer comprising:
a first width extending in a first direction, a first length extending in a second direction, and a first height extending in a third direction; and
a first plurality of passages, wherein each passage of the first plurality of passages comprises an inlet on the first side and an outlet on the second side, wherein each passage of the plurality of passages extends from the inlet to the outlet, and wherein each passage of the first plurality of passages comprises a hexagonal profile;
a second layer comprising:
a second width extending in the first direction, a second length extending in the second direction, and a second height extending in the third direction; and
a second plurality of passages extending from the first side to the second side, wherein each passage of the second plurality of passages comprises a hexagonal profile;
wherein:
the first and second plurality of passages are adjacent to one another;
the first and second plurality of passages comprise a sinusoidal profile in the third direction; and
the first and second plurality of passages comprise a sinusoidal profile in the first direction;
wherein at least one of the passages of the first plurality of passages and at least one of the passages of the second plurality of passages each have a plurality of columns located therein, the columns spaced apart from one another and extending along the length of their respective passages, and the columns extending across their respective passages.
11. A heat exchanger core comprising:
a first side;
a second side opposite the first side;
a third side;
a fourth side opposite the third side, wherein the third and fourth sides each extend from the first side to the second side;
a first layer comprising:
a first width extending in a first direction, a first length extending in a second direction, and a first height extending in a third direction;
a first plurality of passages, wherein each passage of the first plurality of passages comprises an inlet on the first side and an outlet on the second side, wherein each passage of the first plurality of passages extends from the inlet to the outlet, and wherein each passage of the first plurality of passages comprises a hexagonal cross-sectional profile;
a second layer comprising:
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a second width extending in the first direction, a second length extending in the second direction, and a second height extending in the third direction;
a second plurality of passages extending from the first side to the second side, wherein each passage of the second plurality of passages comprises a hexagonal cross-sectional profile;
wherein:
the first and second plurality of passages are adjacent to one another;
the first and second plurality of passages each comprise a first profile in the third direction defined by:
where y1 is the first profile in the third direction, y0
the first and second plurality of passages each comprise a second profile in the first direction defined by:
where x1 is the second profile in the first direction, x0 is a second origination point, Ax is a second amplitude, z1 is a position in the second direction, and dz,x is a second wavelength;
wherein at least one of the passages of the first plurality of passages and at least one of the passages of the second plurality of passages each have a plurality of columns located therein, the columns spaced apart from one another and extending along the length of their respective passages, and the columns extending across their respective passages.
2. The heat exchanger core of
3. The heat exchanger core of
4. The heat exchanger core of
5. The heat exchanger core of
6. The heat exchanger core of
7. The heat exchanger core of
8. The heat exchanger core of
9. The heat exchanger core of
10. The heat exchanger core of
14. The heat exchanger core of
an arch defined by:
where zarch is a profile of the arch for the at least one column, z0 is a starting position in the second direction, Aarch is the amplitude, y is a position in the third direction, and darch is the wavelength.
where yarch is the macro-scale form factor in the third direction, y0
where y is the macro-scale form factor in the third direction, y0
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The present disclosure relates to heat exchangers, and in particular to heat exchanger cores.
Heat exchangers are often used to transfer heat between two fluids. For example, on aircraft, heat exchangers are used to transfer heat between a relatively hot air source, e.g., bleed air from a gas turbine engine, and a relatively cool air source, e.g., ram air. Heat exchangers built for aircraft must be compact yet provide enough heat transfer surface area for adequate heat transfer. Maximizing the heat transfer surface area increases the effectiveness of the heat exchanger.
In one example, a heat exchanger core including a first side, a second side, opposite the first side, a third side, and a fourth side, opposite third side. The third and fourth side extend from the first side to the second side. A first layer includes a first width extending in a first direction, a first length extending in a second direction, a first height extending in a third direction, and a first plurality of passages. Each passage of the first plurality of passages includes an inlet on the first side and an outlet on the second side and extends from the inlets to the outlets. Each passage of the first plurality of passages includes a hexagonal profile. A second layer includes a second width extending in the first direction, a second length extending in the second direction, a second height extending in the third direction, and a second plurality of passages extending from the first side to the second side. Each passage of the second plurality of passages includes a hexagonal profile. The first and second plurality of passages are adjacent to one another. The first and second plurality of passages include a sinusoidal profile in the third direction, and the first and second plurality of passages include a sinusoidal profile in the first direction.
In another example, a heat exchanger core includes a first side, a second side opposite the first side, a third side, and a fourth side opposite the third side. The third and fourth sides each extend from the first side to the second side. A first layer includes a first width extending in a first direction, a first length extending in a second direction, a first height extending in a third direction, and a first plurality of passages. Each passage of the first plurality of passages includes an inlet on the first side and an outlet on the second side. Each passage of the first plurality of passages extends from the inlet to the outlet and includes a hexagonal cross-sectional profile. A second layer includes a second width extending in the first direction, a second length extending in the second direction, and a second height extending in the third direction, and a second plurality of passages extending from the first side to the second side. Each passage of the second plurality of passages comprises a hexagonal cross-sectional profile. The first and second plurality of passages are adjacent to one another. The first and second plurality of passages each comprise a first profile in the third direction defined by:
where y1 is the first profile in the third direction, y0
where x1 is the second profile in the first direction, x0 is a second origination point, Ax is a second amplitude, z1 is a position in the second direction, and dz,x is a second wavelength.
In another example, a heat exchanger core includes a first layer including a first width extending in a first direction, a first length extending in a second direction, and a first height extending in a third direction. A first plurality of passages extending in the second direction. Each passage of the first plurality of passages includes an inlet opposite an outlet. Each passage of the plurality of passages extends from the inlet to the outlet. A second layer includes a second width extending in the first direction, a second length extending in the second direction, and a second height extending in the third direction, and a second plurality of passages extending in the second direction. The first and second plurality of passages are adjacent to one another. The first and second plurality of passages comprise a first sinusoidal profile in the third direction and a second sinusoidal profile in the first direction.
While the above-identified figures set forth one or more embodiments of the present disclosure, other embodiments are also contemplated, as noted in the discussion. In all cases, this disclosure presents embodiments by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art, which fall within the scope and spirit of the principles of the disclosure. The figures may not be drawn to scale, and applications and embodiments of the present disclosure may include features and components not specifically shown in the drawings.
The present disclosure relates to a heat exchanger core. The heat exchanger core includes at least a first layer and a second layer. Both the first and second layers include a plurality of passages, which are hexagonal in shape and extend lengthwise through the heat exchanger core from a first side to a second side. The hexagonal shape of the plurality of passages increases the surface area between the first and second layers. The increased surface area between the first and second layers increases the heat transfer therebetween. The plurality of passages of the first and second layers each include a first sinusoidal profile with an amplitude in a widthwise direction of the core and a second sinusoidal profile with an amplitude in a height-wise direction of the core. The first and second sinusoidal profiles increase the surface area between the first and second layers. The increased surface area between the first and second layers increases the heat transfer therebetween. The heat exchanger core will be discussed with reference to
First side 12 of heat exchanger core 10 is opposite second side 14. Third side 16 is opposite fourth side 18 and third side 16 and fourth side 18 extend from first side 12 to second side 14. First layer 20 has a width extending in first direction X, a length extending in second direction Z, and a height extending in third direction Y. Each of passages 24 extends in second direction Z from inlet 26 to outlet 28. First layer 20 is adjacent second layer 22. Second layer 22 has a width extending in first direction X, a length extending in second direction Z, and a height extending in third direction Y. Each of passages 30 extends in second direction Z from inlet 32 to outlet 34.
In one example, first layer 20 can direct a hot fluid, e.g., bleed air from a gas turbine engine, through passages 24 from inlets 26 to outlets 28. Second layer 22 can direct a cold fluid, e.g., ram air, through passages 30 from inlets 32 to outlets 34. In another example, first layer 20 can direct a cold fluid, e.g., ram air, through passages 24. Second layer 22 can direct a hot fluid, e.g., bleed air from a gas turbine engine, through passages 30.
In one example, layers (20 and 22) can have inlets 32 on first side 12 and outlets 34 on second side 14. In another example, first layer 20 can have inlet 32 on first side 12 and outlet 34 on second side 14 and second layer 22 can have inlet 32 on second side 14 and outlet on first side 12. In another example, first layer 20 can have inlet 32 on second side 14, and outlet 34 on first side 12 and second layer 22 can have inlet 32 on first side 12 and outlet 34 on second side 14.
In the example shown in
As shown in
Profile y1 is the first sinusoidal profile that defines passages (24 and 30) in third direction Y. Origination point y0
Profile x1 is the second sinusoidal profile that defines passages (24 and 30) in first direction X. Origination point x0 is an origination point for profile x1. Amplitude Ax is an amplitude for profile x1 that extends in first direction X. Amplitude Ax can be adjusted to influence the heat transfer between first and second layers (20 and 22). For instance, increasing amplitude Ax increases the surface area between passages (24 and 30) by increasing a flow length of each of passages (24 and 30) between first side 12 and second side 14. The increased surface area between passages (24 and 30) increases the heat transfer between first and second layers (20 and 22). Decreasing amplitude Ax decreases the surface area between passages (24 and 30) by decreasing the flow length of each of passages (24 and 30) between first side 12 and second side 14. The decreased surface area between passages (24 and 30) decreases the heat transfer between first and second layers (20 and 22). Position z1 is a position along profile x1 in second direction Z. Wavelength dz,x is the wavelength of profile x1 in second direction Z. Wavelength dz,x can also be adjusted to influence the heat transfer between first and second layers (20 and 22). For instance, decreasing wavelength dz,y increases the frequency of profile x1. Increasing the frequency of profile x1 increases the flow length of passages (24 and 30) between first side 12 and second side 14. Increasing the flow length of passages (24 and 30) between first side 12 and second side 14 increases the surface area between passages (24 and 30). The increased surface area between passages (24 and 30) increases the heat transfer between first and second layers (20 and 22). Increasing wavelength dz,x decreases the frequency of profile x1. Decreasing the frequency of profile x1 decreases the flow length of passages (24 and 30) between first side 12 and second side 14. Decreasing the flow length of passages (24 and 30) between first side 12 and second side 14 decreases the surface area between passages (24 and 30). The decreased surface area between passages (24 and 30) decreases the heat transfer between first and second layers (20 and 22).
In the example shown in
Columns 40 and fins 42 are within passages (24 and 30). Columns 40 and fins 42 increase the surface area of first and second plurality of passages (24 and 30), which improves the heat transfer between first and second layers (20 and 22). Each of columns 40 and fins 42 generates turbulent flow within passages (24 and 30). When turbulent flow occurs within passages (24 and 30) there is improved heat transfer between first and second layers (20 and 22).
The diameter of columns 40 influences the heat transfer between first and second layers (20 and 22). For instance, increasing the diameter increases the surface area of passages (24 and 30) and increases the resistance to flow through passages (24 and 30). Therefore, there is more heat transfer between first and second layers (20 and 22). Decreasing the diameter decreases the surface area of first and second plurality of passages (24 and 30). Additionally, decreasing the diameter decreases the resistance of flow through passages (24 and 30). Therefore, there is less heat transfer between first and second layers (20 and 22). The size of the diameter can also be controlled and adjusted during the design process of heat exchanger core 10 to tailor heat exchanger core 10 toward a desired performance level.
Increasing the number of columns 40 increases the surface area of passages (24 and 30). In contrast, decreasing the number of columns 40 decreases the surface area of passages (24 and 30). In the example of
Referring to
Fins 42 influence the heat transfer between first and second layers (20 and 22). For instance, the thickness, the width, or the number of fins 42 increases the surface area of fins 42 and thereby increases the surface area of passages (24 and 30). Decreasing the thickness, the width, or the number of fins 42 decreases the surface area of fins 42 and thereby decreases the surface area of passages (24 and 30). As discussed above, increasing or decreasing the surface area of passages (24 and 30) increases or decreases the heat transfer between first and second layers (20 and 22), respectively. In other examples, heat exchanger 10 can include a mixture of columns 40 and fins 42.
In the example of
Profile zarch is a profile used to shape columns 40 in second direction Z. Origination point z0 is a starting position for profile zarch in second direction Z. Amplitude Aarch is the amplitude of profile zarch in second direction Z. Position y is a position in third direction Y. Wavelength darch is the wavelength for profile zarch in third direction Y. Amplitude Aarch influences first and second angles (θ1 and θ2) and bend 66. Increasing amplitude Aarch decreases first and second angles (θ1 and θ2). Decreasing amplitude Aarch increases first and second angles (θ1 and θ2). Amplitude Aarch can be defined as a function of channel alignment with a build direction for additively manufacturing heat exchanger core 10 in the following field function:
Aarch=Aarchmax(·)
When the channel alignment of passages 24 is aligned with the build direction of heat exchanger core 10 in second direction Z, amplitude Aarch will have a large value so as to impart a large amount of bending/arching in columns 40 such that columns 40 are self-supporting during additive manufacturing. When the build direction is in third direction Y and perpendicular to channel alignment of passages 24, Aarch will have a small value such that columns 40 are built straight or nearly straight during additive manufacturing. By using the field function, amplitude Aarch adjusts the design of columns 40 to respond to manufacturing decisions when building heat exchanger core 10. While the example of
Each of the examples discussed above with reference to
Profile yarch, is the macro-scale profile for heat exchanger core 10 in third direction Y. Origination point y0
Amplitude Aarch of profile yarch can be adjusted to influence heat exchanger core 10. For instance, increasing amplitude Aarch of profile yarch increases the surface area of the passages in heat exchanger core 10 by increasing the flow length of the passages. The increased surface area between the passages increases the heat transfer between the layers of heat exchanger core 10. Decreasing amplitude Aarch of profile yarch decreases the surface area between the passages by decreasing the flow length of the passages. The decreased surface area between the passages decreases the heat transfer between the layers of heat exchanger core 10. Amplitude Aarch can also be adjusted to fit core 10 within a defined envelope. The defined envelope is the space of which core 10 must fit within. The defined envelope is a constraint within the system that includes core 10.
Wavelength darch of profile yarch also can be adjusted to influence heat exchanger core 10. For instance, increasing wavelength darch of profile yarch increases the length of the layers of heat exchanger core 10. The increase in length of the layers increases the surface area between the passages. The increased surface area between the passages increases the heat transfer between the layers of heat exchanger core 10. In contrast, decreasing wavelength darch of profile yarch decreases the length of the layers. The decrease in length of the layers decreases the surface area between the passages. The decreased surface area between the passages decreases the heat transfer between the layers. Thus, the values for the sinusoidal macro-profile equation of profile yarch can be adjusted and controlled to tailor the geometry of heat exchanger core 10 to achieve a desired performance level. Wavelength darch can also be adjusted to fit core 10 within the defined envelope.
Profile y represents the macro-scale logistic sigmoid curve in third direction Y. Origination point y0
Maximum value L can influence heat exchanger core 10. For instance, increasing maximum value L increases the overall height of heat exchanger core 10 in third direction Y, which increases the surface area between the passages of heat exchanger core 10. The increased surface area between the passages increases the heat transfer between the layers of heat exchanger core 10. Conversely, decreasing maximum value L decreases the overall height of heat exchanger core 10 in third direction Y, which decreases the surface area between the passages. The decreased surface area between the passages decreases the heat transfer between the layers of heat exchanger core 10.
Steepness k also influences heat exchanger core 10. Steepness k affects how quickly profile Y goes from a minimum value, to a maximum value. Increasing steepness k increases the rate of change between the minimum value and the maximum value. Increasing the rate of change between the minimum and maximum values would influence add an interruption to passages (24 and 30). The added interruption would increase pressure drop across core 10. In contrast, decreasing steepness k would have a more gradual rate of change between the minimum value and the maximum value. Decreasing the rate of change between the minimum value and the maximum value would decrease the interruption within passages (20 and 30). The decreased interruption would decrease pressure drop across core 10. Furthermore, steepness k can be changed to conform core 10 within the defined envelope.
In the examples of
Discussion of Possible Embodiments
The following are non-exclusive descriptions of possible embodiments of the present invention.
In one example, a heat exchanger core including a first side, a second side, opposite the first side, a third side, and a fourth side, opposite third side. The third and fourth side extend from the first side to the second side. A first layer includes a first width extending in a first direction, a first length extending in a second direction, a first height extending in a third direction, and a first plurality of passages. Each passage of the first plurality of passages includes an inlet on the first side and an outlet on the second side and extends from the inlets to the outlets. Each passage of the first plurality of passages includes a hexagonal profile. A second layer includes a second width extending in the first direction, a second length extending in the second direction, a second height extending in the third direction, and a second plurality of passages extending from the first side to the second side. Each passage of the second plurality of passages includes a hexagonal profile. The first and second plurality of passages are adjacent to one another. The first and second plurality of passages include a sinusoidal profile in the third direction, and the first and second plurality of passages include a sinusoidal profile in the first direction.
The heat exchanger core of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:
wherein the sinusoidal profile in the third direction comprises a first amplitude;
wherein the sinusoidal profile in the first direction comprises a second amplitude
wherein the first amplitude comprises a magnitude that is different from a magnitude of the second amplitude;
further comprising a plurality of columns inside at least one passage of the first plurality of passages or at least one passage of the second plurality of passages, wherein the plurality of columns are spread apart from one another in the second direction, and each column of the plurality of columns extends in the third direction;
wherein at least one column of the plurality of columns comprises a bend in the at least one column between a first portion of the at least one column and a second portion of the at least one column, wherein the first portion extends from a wall of the first or second plurality of passages at a first angle, and wherein the second portion extends from the wall of the first or second plurality of passages at a second angle;
wherein the first angle is between 5 degrees and 55 degrees, and wherein the second angle is between 5 degrees and 55 degrees;
wherein at least one column of the plurality of columns is a fin, wherein the fin extends from a leading edge to a trailing edge in the second direction;
wherein the heat exchanger core further comprises a macro-scale form factor comprising a sinusoidal macro-profile; and/or
wherein the sinusoidal macro-profile comprises an amplitude in the third direction;
wherein the heat exchanger core further comprises a macro-scale form factor comprising a logistic sigmoid curve.
In another example, a heat exchanger core includes a first side, a second side opposite the first side, a third side, and a fourth side opposite the third side. The third and fourth sides each extend from the first side to the second side. A first layer includes a first width extending in a first direction, a first length extending in a second direction, a first height extending in a third direction, and a first plurality of passages. Each passage of the first plurality of passages includes an inlet on the first side and an outlet on the second side. Each passage of the first plurality of passages extends from the inlet to the outlet and includes a hexagonal cross-sectional profile. A second layer includes a second width extending in the first direction, a second length extending in the second direction, and a second height extending in the third direction, and a second plurality of passages extending from the first side to the second side. Each passage of the second plurality of passages comprises a hexagonal cross-sectional profile. The first and second plurality of passages are adjacent to one another. The first and second plurality of passages each comprise a first profile in the third direction defined by:
where y1 is the first profile in the third direction, y0
where x1 is the second profile in the first direction, x0 is a second origination point, Ax is a second amplitude, z1 is a position in the second direction, and dz,x is a second wavelength.
The heat exchanger core of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:
wherein the first and second amplitude are not equal;
wherein the first and second wavelength are not equal;
further comprising a plurality of columns inside at least one passage of the first plurality of passages or at least one passage of the second plurality of passages, wherein the plurality of columns are spread apart from one another in the second direction, and each column of the plurality of columns extends in the third direction
wherein at least one column of the plurality of columns comprises:
an arch defined by:
where zarch is a profile of the arch for the at least one column, z0 is a starting position in the second direction, Aarch is the amplitude, y is a position in the third direction, and darch is the wavelength;
further comprising a macro-scale form factor defined by:
where yarch is the macro-scale form factor in the third direction, y0
further comprising a macro-scale form factor defined by:
where y is the macro-scale form factor in the third direction, y0
In another example, a heat exchanger core includes a first layer including a first width extending in a first direction, a first length extending in a second direction, and a first height extending in a third direction. A first plurality of passages extending in the second direction. Each passage of the first plurality of passages includes an inlet opposite an outlet. Each passage of the plurality of passages extends from the inlet to the outlet. A second layer includes a second width extending in the first direction, a second length extending in the second direction, and a second height extending in the third direction, and a second plurality of passages extending in the second direction. The first and second plurality of passages are adjacent to one another. The first and second plurality of passages comprise a first sinusoidal profile in the third direction and a second sinusoidal profile in the first direction.
The heat exchanger core of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:
wherein the first sinusoidal profile comprises a first amplitude extending in the third direction and the second sinusoidal profile comprises a second amplitude extending in the first direction.
While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. For example, while passages (24 and 30) have been described as having a hexagonal cross-sectional profile. In other embodiments, passages (24 and 30) can has any shape as a cross-sectional profile. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.
Lynch, Matthew E., Binek, Lawrence A., Butcher, Evan J.
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